diff --git a/python/BUILD.md b/python/BUILD.md
index d61aadb..66de0f5 100644
--- a/python/BUILD.md
+++ b/python/BUILD.md
@@ -14,7 +14,7 @@ Run the following commands to generate a distributable source package:
 
 ```
 python -m pip install --upgrade build
-python -m build --dist
+python -m build --sdist
 ```
 
 ### Why not .whl?
diff --git a/python/saleae/automation/manager.py b/python/saleae/automation/manager.py
index 1389a8d..9b02a64 100644
--- a/python/saleae/automation/manager.py
+++ b/python/saleae/automation/manager.py
@@ -314,9 +314,10 @@ def cleanup():
 
     @classmethod
     def launch(cls,
-              application_path: Optional[Union[Path, str]] = None, 
+               application_path: Optional[Union[Path, str]] = None,
                connect_timeout_seconds: Optional[float] = None,
-               grpc_channel_arguments: Optional[List[Tuple[str, Any]]] = None) -> 'Manager':
+               grpc_channel_arguments: Optional[List[Tuple[str, Any]]] = None,
+               port: Optional[int] = None) -> 'Manager':
         """
         Launch the Logic2 application and shut it down when the returned Manager is closed.
 
@@ -324,6 +325,7 @@ def launch(cls,
                                  a locally installed copy of Logic2 will be searched for.
         :param connect_timeout_seconds: See __init__
         :param grpc_channel_arguments: See __init__
+        :param port: Port to use for the gRPC server. If not specified, 10430 will be used.
 
         """
 
@@ -357,7 +359,10 @@ def fail(reason: str):
             if not os.path.exists(logic2_bin):
                 fail(f'application path "{application_path}" does not exist')
 
-        process = subprocess.Popen([logic2_bin, '--automation', '--automationPort', str(_DEFAULT_GRPC_PORT)],
+        if port is None:
+            port = _DEFAULT_GRPC_PORT
+
+        process = subprocess.Popen([logic2_bin, '--automation', '--automationPort', str(port)],
                                    stdout=subprocess.DEVNULL,
                                    stderr=subprocess.DEVNULL)
 
@@ -383,7 +388,7 @@ def fail(reason: str):
 
         return cls(
             address=_DEFAULT_GRPC_ADDRESS,
-            port=_DEFAULT_GRPC_PORT,
+            port=port,
             logic2_process=process,
             connect_timeout_seconds=connect_timeout_seconds,
             grpc_channel_arguments=grpc_channel_arguments)
diff --git a/python/tests/conftest.py b/python/tests/conftest.py
index be1fc48..5cfd351 100644
--- a/python/tests/conftest.py
+++ b/python/tests/conftest.py
@@ -7,6 +7,7 @@
 def pytest_addoption(parser):
     parser.addoption('--use-existing', action='store_true')
     parser.addoption('--app-path', action='store')
+    parser.addoption('--port', action='store', type=int)
 
 @pytest.fixture
 def asset_path() -> str:
@@ -16,13 +17,15 @@ def asset_path() -> str:
 @pytest.fixture(scope='session')
 def manager(request):
     app_path = request.config.getoption('--app-path')
+
+    port = request.config.getoption('--port')
     if app_path is not None:
-        with saleae.automation.Manager.launch(app_path) as mgr:
+        with saleae.automation.Manager.launch(app_path, port=port) as mgr:
             yield mgr
         pass
     elif request.config.getoption('--use-existing'):
-        with saleae.automation.Manager.connect(port=10430) as mgr:
+        with saleae.automation.Manager.connect(port=port) as mgr:
             yield mgr
     else:
-        with saleae.automation.Manager.launch() as mgr:
+        with saleae.automation.Manager.launch(port=port) as mgr:
             yield mgr
diff --git a/python/tests/load_save_test.py b/python/tests/load_save_test.py
index a2a9abe..36dae38 100644
--- a/python/tests/load_save_test.py
+++ b/python/tests/load_save_test.py
@@ -1,5 +1,4 @@
 import os.path
-from tkinter import E
 
 import saleae.automation